A Study of Conduction Band Edge States in Complex Oxides By X-Ray Absorption Spectroscopy

Effects of sulfation level on the desulfation behavior of pre-sulfated Pt BaO/Al2O3 lean NOx trap catalysts: a combined H2 Temperature-Programmed Reaction, in-situ sulfur K-edge X-ray Absorption Near-Edge Spectroscopy, X-ray Photoelectron Spectroscopy, and Time-Resolved X-ray Diffraction Study

Kim, Do Heui ; Szanyi, Janos ; Kwak, Ja Hun ; ... April 2009 - Journal of Physical Chemistry C, 113(17):7336-7341

Desulfation by hydrogen of pre-sulfated Pt(2wt%) BaO(20wt%)/Al2O3 with various sulfur loading (S/Ba = 0.12, 0.31 and 0.62) were investigated by combining H2 temperature programmed reaction (TPRX), x-ray photoelectron spectroscopy (XPS), in-situ sulfur K-edge x-ray absorption near-edge spectroscopy (XANES), and synchrotron time-resolved x-ray diffraction (TR-XRD) techniques. We find that the amount of H2S desorbed during the desulfation in the H2 TPRX experiments is not proportional to the amount of initial sulfur loading. The results of both in-situ sulfur K-edge XANES and TR-XRD show that at low sulfur loadings, sulfates were transformed to a BaS phase and remained in the catalyst, rathermore »« less
DOI: 10.1021/jp900304h
Effects of Sulfation Level on the Desulfation Behavior of Presulfated Pt-BaO/Al2O3 Lean NOx Trap Catalysts: A Combined H2 Temperature-Programmed Reaction, in Situ Sulfur K-Edge X-ray Absorption Near-Edge Spectroscopy, X-ray Photoelectron Spectroscopy, and Time-Resolved X-ray Diffraction Study

Kim, D.H. ; Hanson, J. ; Szanyi, J. ; ... April 2009 - Journal of Physical Chemistry C

Desulfation by hydrogen of presulfated Pt (2 wt %)-BaO(20 wt %)/Al{sub 2}O{sub 3} with various sulfur loading (S/Ba = 0.12, 0.31, and 0.62) were investigated by combining H{sub 2} temperature programmed reaction (TPRX), X-ray photoelectron spectroscopy (XPS), in situ sulfur K-edge X-ray absorption near-edge spectroscopy (XANES), and synchrotron time-resolved X-ray diffraction (TR-XRD) techniques. We find that the amount of H{sub 2}S desorbed during the desulfation in the H{sub 2} TPRX experiments is not proportional to the amount of initial sulfur loading. The results of both in situ sulfur K-edge XANES and TR-XRD show that at low sulfur loadings, sulfates weremore »« less
DOI: 10.1021/jp900304h
Study of oxidation states of the transition metals in a series of Prussian blue analogs using x-ray absorption near edge structure (XANES) spectroscopy

Adak, S. ; Hartl, M. ; Daemen, L. ; ... January 2017 - Journal of Electron Spectroscopy and Related Phenomena
Cited by 2
DOI: 10.1016/j.elspec.2016.11.011
Study of oxidation states of the transition metals in a series of Prussian blue analogs using x-ray absorption near edge structure (XANES) spectroscopy

Adak, S. ; Hartl, M. ; Daemen, L. ; ... January 2017 - Journal of Electron Spectroscopy and Related Phenomena
DOI: 10.1016/j.elspec.2016.11.011
Extended x-ray absorption fine structure spectroscopy and x-ray absorption near edge spectroscopy study of aliovalent doped ceria to correlate local structural changes with oxygen vacancies clustering

Shirbhate, S. C. ; Acharya, S. A., E-mail: saha275@yahoo.com ; Yadav, A. K. April 2016 - Applied Physics Letters

This study provides atomic scale insight to understand the role of aliovalent dopants on oxygen vacancies clustering and dissociation mechanism in ceria system in order to enhance the performance of oxy-ion conductor. Dopants induced microscale changes in ceria are probed by extended X-ray absorption fine structure spectroscopy, X-ray absorption near edge spectra, and Raman spectroscopy. The results are explored to establish a correlation between atomic level structural changes (coordination number, interatomic spacing) → formation of dimer and trimer type cation-oxygen vacancies defect complex (intrinsic and extrinsic) → dissociation of oxygen vacancies from defect cluster → ionic conductivity temperature. It ismore »« less
DOI: 10.1063/1.4945098

Title: A Study of Conduction Band Edge States in Complex Oxides By X-Ray Absorption Spectroscopy

Abstract

Citation Formats

Effects of sulfation level on the desulfation behavior of pre-sulfated Pt BaO/Al2O3 lean NOx trap catalysts: a combined H2 Temperature-Programmed Reaction, in-situ sulfur K-edge X-ray Absorption Near-Edge Spectroscopy, X-ray Photoelectron Spectroscopy, and Time-Resolved X-ray Diffraction Study

Effects of Sulfation Level on the Desulfation Behavior of Presulfated Pt-BaO/Al2O3 Lean NOx Trap Catalysts: A Combined H2 Temperature-Programmed Reaction, in Situ Sulfur K-Edge X-ray Absorption Near-Edge Spectroscopy, X-ray Photoelectron Spectroscopy, and Time-Resolved X-ray Diffraction Study

Study of oxidation states of the transition metals in a series of Prussian blue analogs using x-ray absorption near edge structure (XANES) spectroscopy

Study of oxidation states of the transition metals in a series of Prussian blue analogs using x-ray absorption near edge structure (XANES) spectroscopy

Extended x-ray absorption fine structure spectroscopy and x-ray absorption near edge spectroscopy study of aliovalent doped ceria to correlate local structural changes with oxygen vacancies clustering